// Copyright (c) 2012 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef UI_VIEWS_CONTROLS_SCROLLBAR_NATIVE_SCROLL_BAR_VIEWS_H_
#define UI_VIEWS_CONTROLS_SCROLLBAR_NATIVE_SCROLL_BAR_VIEWS_H_

#include "base/compiler_specific.h"
#include "base/macros.h"
#include "ui/gfx/geometry/point.h"
#include "ui/native_theme/native_theme.h"
#include "ui/views/controls/button/button.h"
#include "ui/views/controls/scrollbar/base_scroll_bar.h"
#include "ui/views/controls/scrollbar/native_scroll_bar_wrapper.h"
#include "ui/views/view.h"

namespace gfx {
class Canvas;
}

namespace views {

class NativeScrollBar;

// Views implementation for the scrollbar.
class VIEWS_EXPORT NativeScrollBarViews : public BaseScrollBar,
                                          public ButtonListener,
                                          public NativeScrollBarWrapper {
public:
    static const char kViewClassName[];

    // Creates new scrollbar, either horizontal or vertical.
    explicit NativeScrollBarViews(NativeScrollBar* native_scroll_bar);
    ~NativeScrollBarViews() override;

private:
    // View overrides:
    void Layout() override;
    void OnPaint(gfx::Canvas* canvas) override;
    gfx::Size GetPreferredSize() const override;
    const char* GetClassName() const override;

    // ScrollBar overrides:
    int GetLayoutSize() const override;

    // BaseScrollBar overrides:
    void ScrollToPosition(int position) override;
    int GetScrollIncrement(bool is_page, bool is_positive) override;

    // BaseButton::ButtonListener overrides:
    void ButtonPressed(Button* sender, const ui::Event& event) override;

    // NativeScrollBarWrapper overrides:
    int GetPosition() const override;
    View* GetView() override;
    void Update(int viewport_size, int content_size, int current_pos) override;

    // Returns the area for the track. This is the area of the scrollbar minus
    // the size of the arrow buttons.
    gfx::Rect GetTrackBounds() const override;

    // The NativeScrollBar we are bound to.
    NativeScrollBar* native_scroll_bar_;

    // The scroll bar buttons (Up/Down, Left/Right).
    Button* prev_button_;
    Button* next_button_;

    ui::NativeTheme::ExtraParams params_;
    ui::NativeTheme::Part part_;
    ui::NativeTheme::State state_;

    DISALLOW_COPY_AND_ASSIGN(NativeScrollBarViews);
};

} // namespace views

#endif // UI_VIEWS_CONTROLS_SCROLLBAR_NATIVE_SCROLL_BAR_VIEWS_H_
